Objective:This study aimed to analyze the genetic subtypes and drug resistance transmission characteristics of HIV-1 among the preoperative population in Ningxia from 2018 to 2023, to provide a scientific basis for the prevention and control of the AIDS epidemic.Methods:Plasma samples and demographic information of HIV/AIDS patients receiving antiviral treatment in Ningxia from 2018 to 2023 were collected. Blood samples with a viral loads >200 copies/ml from preoperative testing were amplified, sequenced, and subjected to genotypic resistance testing to analyze their genetic subtypes and drug resistance characteristics. The TN93 model in MEGA11 software was used to calculate the genetic distance between each pair of all sequences, and a molecular transmission network was constructed in Cytoscape 3.10.0 with 1.9% as the genetic threshold.Results:Among 101 preoperative HIV/AIDS patients, CRF07_BC and CRF01_AE were the predominant subtypes. The majority were male (85.15%, 86/101), aged 41-60 years (45.54%, 46/101), residing in Yinchuan city (61.39%, 62/101), and infected via heterosexual transmission (71.29%, 72/101), with most cases being late-detected. Of 39 drug-resistant sequences, resistance to non-nucleoside reverse transcriptase inhibitors (NNRTIs) alone (18.81%, 19/101) and dual resistance to nucleoside reverse transcriptase inhibitors (NRTIs)-NNRTIs (13.86%, 14/101) were most common. Among 44 sequences forming 13 transmission clusters, nine clusters harbored drug-resistant mutations. Four subtypes entered the molecular network, primarily involving heterosexual transmission, individuals with junior high school education or below, and men aged≥50 years.Conclusions:From 2018 to 2023, the preoperative HIV/AIDS patients had diversified genetic subtypes, with higher rates of overall drug resistance and late detection, stronger drug resistance and higher mortality rate. Strengthening molecular epidemiological research and developing targeted screening strategies are critical to improve early detection and reduce transmission risks.

Objective:To investigate how age and nail-tract volumetric bone mineral density (vBMD) are associated with postoperative mechanical performance of proximal femoral nail anti-rotation (PFNA-Ⅱ) fixation for geriatric intertrochanteric fractures using a finite-element analysis.Methods:Fifteen elderly patients with intertrochanteric fracture of the femur were selected for this study. They were 11 females and 4 males and divided into 5 groups based on their ages ( n=3): 55-year-old, 65-year-old, 75-year-old, 85-year-old, and 95-year-old groups. After three-dimensional models of the proximal femur were constructed using the preoperative CT data of their healthy contralateral hip, 31-A1.2 fractures of the AO/OTA type were created and PFNA-Ⅱ fixations simulated. Two loading schemes were created: graded quasi-static axial loads (700 N, 1,400 N, 2,100 N, and 2,800 N) were applied to compute equivalent plastic strain volumes in the femoral head region; displacement-controlled loading was applied to failure to derive load-displacement curves for stiffness and the maximum failure load. Nail-tract vBMD and regional hip vBMDs were measured by quantitative CT. Pearson correlation analysis was conducted to investigate the associations of age and nail-tract vBMD with the aforementioned mechanical indicators. Results:Under the same load, compared with the 55-year-old, 65-year-old, and 75-year-old groups, the plastic strain unit volumes of the fracture models in the 85-year-old and 95-year-old groups increased significantly. Under a load of 700 N, no plastic strain was observed in the fracture models in the 55-year-old, 65-year-old, and 75-year-old groups, while an average plastic strain of approximately 50 mm 3 was observed in the fracture models in the 85-year-old group. Under a load of 2,800 N, the high strain areas in the fracture models in the 85-year-old and 95-year-old groups were mainly concentrated at the tip of the head nail and the junction between the head nail and the main nail. Load-displacement curves showed a marked reduction in the failure load in patients aged ≥85 years. Under loads of 1,400 N, 2,100 N, and 2,800 N, there was a strong association between the nail-tract vBMD and the volume of the plastic strain unit ( r=-0.82, -0.88, -0.89, respectively), which was stronger than those for total-hip vBMD. Conclusions:Finite-element analysis indicates that age and nail-tract vBMD are closely related to local plastic strain and overall stiffness of the proximal femur after PFNA-Ⅱ fixation for the geriatric intertrochanteric fractures. Patients aged ≥85 years old are more prone to plastic yielding, which compromises fixation stability.

Objective To investigate the association between intestinal microbiota dysbiosis and colonic polyps,Helicobacter pylori(Hp)infection,and intestinal metaplasia.Methods A total of 200 patients diagnosed with colonic polyps,Hp infection,or both conditions.These patients were classified into three groups:the colonic polyp group(n=90),the Hp infection with intestinal metaplasia group(n=49),and the colonic polyp combined with Hp infection and intestinal metaplasia group(n=61).Additionally,62 individuals who underwent routine health examinations at our hospital during the same period were enrolled as a control group.The study compared gut microbiota imbalances across these groups to investigate the association between intestinal dysbiosis and colonic pol-yps,Hp infection,and the co-occurrence of colonic polyps with Hp-related intestinal metaplasia.Logistic regression analysis was performed to identify risk factors associated with the development of intestinal metaplasia due to Hp infection in patients with colonic polyps.Results Compared to the control group,intestinal flora imbalance was significantly more prevalent in the colorectal polyp group,the Hp infection with intestinal metaplasia group,and the colorectal polyp combined with Hp infection and intestinal metaplasia group(P<0.05).Moreover,intestinal flora imbalance in the colorectal polyp with Hp infection and intestinal metaplasia group was significantly higher than that in both the colorectal polyp group and the Hp infection with intestinal metaplasia group(P<0.05).Regarding exhaled gas levels,H2 and CH4 concentrations were significantly elevated in the groups with colorectal polyps accom-panied by Hp infection and intestinal metaplasia,those with colorectal polyps alone,and those with Hp infection and intestinal metaplasia,compared to the control group(P<0.05).Similarly,exhaled H2S levels were significantly higher in the group with colorectal polyps complicated by Hp infection and intestinal metaplasia than in the control group(P<0.05).Furthermore,exhaled H2 and CH4 levels showed positive correlations with the presence of colorectal polyps,Hp infection with intestinal metaplasia,and colorectal polyps combined with Hp infection and intestinal metaplasia(P<0.05).Exhaled H2S levels were positively correlated with colorectal polyps complicated by Hp infec-tion and intestinal metaplasia(P<0.05).Logistic regression analysis indicated that a history of smoking,atrophic gastritis,peptic ulcer,and intestinal flora imbalance are independent risk factors for Hp infection-associated intesti-nal metaplasia in patients with colorectal polyps(P<0.05).Conclusion Intestinal flora imbalance is associated with colorectal polyps and Hp-induced intestinal metaplasia,suggesting that microbial dysbiosis may represent a potential risk factor for the development of these conditions.

In order to delve into the molecular mechanism underlying the increased pathogenicity of the recombinant Muscovy duck parvovirus(rMDPV)towards Muscovy ducklings,two sub-genom-ic fragments of the rMDPV strain ZW were cloned into the plasmid pBluescript Ⅱ(SK)to gener-ate the recombinant plasmid pZW.A single nucleotide mutation was engineered in the VP3 gene of pZW to discriminate from the parental strain ZW.pZW plasmid-lipid complex was transfected into the chorioallantoic membrane of 11-day-old embryonated Muscovy duck embryos,resulting in res-cue of infectious virus,rZW,carrying the genetic marker.The rescued virus was passaged in 12-day-old embryonated Muscovy duck embryos and exhibited the similar medium embryo lethal dose(ELD50)value and growth curve compared to the parental strain ZW.Both rZW and strain ZW led to 100％mortality in the infection tests performed with 3-day-old Muscovy duckling.Postmortem necropsy revealed a characteristic intestine embolism formed in the rZW-infected ducklings.Taken together,the generation of the infectious clone pZW lays a solid foundation for deciphering the pathogenesis of rMDPV.

Objective To investigate the association between intestinal microbiota dysbiosis and colonic polyps,Helicobacter pylori(Hp)infection,and intestinal metaplasia.Methods A total of 200 patients diagnosed with colonic polyps,Hp infection,or both conditions.These patients were classified into three groups:the colonic polyp group(n=90),the Hp infection with intestinal metaplasia group(n=49),and the colonic polyp combined with Hp infection and intestinal metaplasia group(n=61).Additionally,62 individuals who underwent routine health examinations at our hospital during the same period were enrolled as a control group.The study compared gut microbiota imbalances across these groups to investigate the association between intestinal dysbiosis and colonic pol-yps,Hp infection,and the co-occurrence of colonic polyps with Hp-related intestinal metaplasia.Logistic regression analysis was performed to identify risk factors associated with the development of intestinal metaplasia due to Hp infection in patients with colonic polyps.Results Compared to the control group,intestinal flora imbalance was significantly more prevalent in the colorectal polyp group,the Hp infection with intestinal metaplasia group,and the colorectal polyp combined with Hp infection and intestinal metaplasia group(P<0.05).Moreover,intestinal flora imbalance in the colorectal polyp with Hp infection and intestinal metaplasia group was significantly higher than that in both the colorectal polyp group and the Hp infection with intestinal metaplasia group(P<0.05).Regarding exhaled gas levels,H2 and CH4 concentrations were significantly elevated in the groups with colorectal polyps accom-panied by Hp infection and intestinal metaplasia,those with colorectal polyps alone,and those with Hp infection and intestinal metaplasia,compared to the control group(P<0.05).Similarly,exhaled H2S levels were significantly higher in the group with colorectal polyps complicated by Hp infection and intestinal metaplasia than in the control group(P<0.05).Furthermore,exhaled H2 and CH4 levels showed positive correlations with the presence of colorectal polyps,Hp infection with intestinal metaplasia,and colorectal polyps combined with Hp infection and intestinal metaplasia(P<0.05).Exhaled H2S levels were positively correlated with colorectal polyps complicated by Hp infec-tion and intestinal metaplasia(P<0.05).Logistic regression analysis indicated that a history of smoking,atrophic gastritis,peptic ulcer,and intestinal flora imbalance are independent risk factors for Hp infection-associated intesti-nal metaplasia in patients with colorectal polyps(P<0.05).Conclusion Intestinal flora imbalance is associated with colorectal polyps and Hp-induced intestinal metaplasia,suggesting that microbial dysbiosis may represent a potential risk factor for the development of these conditions.

In order to delve into the molecular mechanism underlying the increased pathogenicity of the recombinant Muscovy duck parvovirus(rMDPV)towards Muscovy ducklings,two sub-genom-ic fragments of the rMDPV strain ZW were cloned into the plasmid pBluescript Ⅱ(SK)to gener-ate the recombinant plasmid pZW.A single nucleotide mutation was engineered in the VP3 gene of pZW to discriminate from the parental strain ZW.pZW plasmid-lipid complex was transfected into the chorioallantoic membrane of 11-day-old embryonated Muscovy duck embryos,resulting in res-cue of infectious virus,rZW,carrying the genetic marker.The rescued virus was passaged in 12-day-old embryonated Muscovy duck embryos and exhibited the similar medium embryo lethal dose(ELD50)value and growth curve compared to the parental strain ZW.Both rZW and strain ZW led to 100％mortality in the infection tests performed with 3-day-old Muscovy duckling.Postmortem necropsy revealed a characteristic intestine embolism formed in the rZW-infected ducklings.Taken together,the generation of the infectious clone pZW lays a solid foundation for deciphering the pathogenesis of rMDPV.

Objective:This study aimed to analyze the genetic subtypes and drug resistance transmission characteristics of HIV-1 among the preoperative population in Ningxia from 2018 to 2023, to provide a scientific basis for the prevention and control of the AIDS epidemic.Methods:Plasma samples and demographic information of HIV/AIDS patients receiving antiviral treatment in Ningxia from 2018 to 2023 were collected. Blood samples with a viral loads >200 copies/ml from preoperative testing were amplified, sequenced, and subjected to genotypic resistance testing to analyze their genetic subtypes and drug resistance characteristics. The TN93 model in MEGA11 software was used to calculate the genetic distance between each pair of all sequences, and a molecular transmission network was constructed in Cytoscape 3.10.0 with 1.9% as the genetic threshold.Results:Among 101 preoperative HIV/AIDS patients, CRF07_BC and CRF01_AE were the predominant subtypes. The majority were male (85.15%, 86/101), aged 41-60 years (45.54%, 46/101), residing in Yinchuan city (61.39%, 62/101), and infected via heterosexual transmission (71.29%, 72/101), with most cases being late-detected. Of 39 drug-resistant sequences, resistance to non-nucleoside reverse transcriptase inhibitors (NNRTIs) alone (18.81%, 19/101) and dual resistance to nucleoside reverse transcriptase inhibitors (NRTIs)-NNRTIs (13.86%, 14/101) were most common. Among 44 sequences forming 13 transmission clusters, nine clusters harbored drug-resistant mutations. Four subtypes entered the molecular network, primarily involving heterosexual transmission, individuals with junior high school education or below, and men aged≥50 years.Conclusions:From 2018 to 2023, the preoperative HIV/AIDS patients had diversified genetic subtypes, with higher rates of overall drug resistance and late detection, stronger drug resistance and higher mortality rate. Strengthening molecular epidemiological research and developing targeted screening strategies are critical to improve early detection and reduce transmission risks.

Objective:To investigate how age and nail-tract volumetric bone mineral density (vBMD) are associated with postoperative mechanical performance of proximal femoral nail anti-rotation (PFNA-Ⅱ) fixation for geriatric intertrochanteric fractures using a finite-element analysis.Methods:Fifteen elderly patients with intertrochanteric fracture of the femur were selected for this study. They were 11 females and 4 males and divided into 5 groups based on their ages ( n=3): 55-year-old, 65-year-old, 75-year-old, 85-year-old, and 95-year-old groups. After three-dimensional models of the proximal femur were constructed using the preoperative CT data of their healthy contralateral hip, 31-A1.2 fractures of the AO/OTA type were created and PFNA-Ⅱ fixations simulated. Two loading schemes were created: graded quasi-static axial loads (700 N, 1,400 N, 2,100 N, and 2,800 N) were applied to compute equivalent plastic strain volumes in the femoral head region; displacement-controlled loading was applied to failure to derive load-displacement curves for stiffness and the maximum failure load. Nail-tract vBMD and regional hip vBMDs were measured by quantitative CT. Pearson correlation analysis was conducted to investigate the associations of age and nail-tract vBMD with the aforementioned mechanical indicators. Results:Under the same load, compared with the 55-year-old, 65-year-old, and 75-year-old groups, the plastic strain unit volumes of the fracture models in the 85-year-old and 95-year-old groups increased significantly. Under a load of 700 N, no plastic strain was observed in the fracture models in the 55-year-old, 65-year-old, and 75-year-old groups, while an average plastic strain of approximately 50 mm 3 was observed in the fracture models in the 85-year-old group. Under a load of 2,800 N, the high strain areas in the fracture models in the 85-year-old and 95-year-old groups were mainly concentrated at the tip of the head nail and the junction between the head nail and the main nail. Load-displacement curves showed a marked reduction in the failure load in patients aged ≥85 years. Under loads of 1,400 N, 2,100 N, and 2,800 N, there was a strong association between the nail-tract vBMD and the volume of the plastic strain unit ( r=-0.82, -0.88, -0.89, respectively), which was stronger than those for total-hip vBMD. Conclusions:Finite-element analysis indicates that age and nail-tract vBMD are closely related to local plastic strain and overall stiffness of the proximal femur after PFNA-Ⅱ fixation for the geriatric intertrochanteric fractures. Patients aged ≥85 years old are more prone to plastic yielding, which compromises fixation stability.

With the advancement of synthetic biology, recombinant proteins are poised to play a significant role in medical applications. The scaled manufacturing is a pillar for the extensive application and development of recombinant proteins across various fields. In the large-scale production process of recombinant proteins, the removal and detection of endotoxins are essential to reduce their levels to safe thresholds in the final products. Currently, establishing stringent endotoxin limits for different recombinant protein products is a crucial aspect of safety assessment. This review begins by shedding light on the pathogenicity of endotoxins and discusses the methods for the removal and determination of endotoxins during the production processes of recombinant proteins. Subsequently, this review summarizes the endotoxin limits in industries such as biologics, medical devices, and human recombinant DNA products, particularly those in recombinant protein injection products. It is highlighted that regardless of whether the hosts for recombinant protein expression are bacteria or not, endotoxin testing is required for the final products of injectable recombinant proteins, and compliance with relevant industry standards is necessary. This review aims to provide a reference for the research on endotoxins in the large-scale production process of recombinant proteins.
Endotoxins/genetics* ; Recombinant Proteins/genetics* ; Humans ; Drug Contamination/prevention & control*

Objective:To provide evidence-based recommendations for the prevention and management of lower limb ischemia in veno-arterial extracorporeal membrane oxygenation (VA-ECMO) patients during treatment according to search, evaluate, and summarize the best evidence on the prevention and management of lower limb ischemia in patients with VA-ECMO.Methods:Based on the PIPOST framework (population, intervention, professional, outcome, setting, and type of evidence), an evidence-based question was formulated. A systematic search was conducted according to the "6S" evidence pyramid model in both domestic and international databases, as well as professional association websites, for all evidence related to the prevention and management of lower limb ischemia in VA-ECMO patients (aged ≥18 years). The types of evidence included clinical decisions, guidelines, expert consensus, systematic reviews, evidence summaries, and original studies. The search was conducted from the construction of the databases to February 2024. Two researchers independently conducted a literature quality evaluation, extracted and summarized evidence from the studies that met the quality criteria.Results:A total of 13 articles were included, consisting of 3 clinical decisions, 3 guidelines, 3 expert consensus, 3 systematic reviews, and 1 randomized controlled trial. A total of 18 pieces of evidence in 7 dimensions were summarized, including risk factors of VA-ECMO lower limb ischemia, evaluation before catheterization, evaluation and monitoring during treatment, prevention of lower limb ischemia, treatment of lower limb ischemia, management of distal perfusion catheter (DPC), and monitoring after VA-ECMO weaning.Conclusion:This evidence summary provides evidence-based recommendations for the prevention and management of lower limb ischemia in VA-ECMO patients, aiming to assist clinical healthcare professionals in developing tailored strategies for the prevention and management of lower limb ischemia based on during VA-ECMO support.